# Circuit Theory/Thevenin-Norton

From Wikibooks, open books for an open world

## Contents

## Vth using Node[edit]

## In using Node[edit]

## Rth or Rn[edit]

## Finding Rth using source injection and node[edit]

Here is the mupad/matlab code that generates the answer R_{th} = 6.0591 ohms.

## Comparing Node with Thevenin Equivalent[edit]

Solving the node equations yields:

Using the Thevenin equivalent (and voltage divider) to compute voltage across the 12 ohm resistor:

So they match ...

Thevenin voltage and resistance can not be computed from a node analysis of the entire circuit, but the node analysis of the entire circuit can be used to check if the thevenin equivalent produces the same numbers.